protected override (SegmentationStatus status, ReadOnlySequence <byte>?segment) Read(ReadOnlySequence <byte> buffer)
{
var startOfSegment = Starts.Select(start => buffer.PositionOf(start)).FirstOrDefault(start => start != null);
if (startOfSegment != null)
{
var segment = buffer.Slice(startOfSegment.Value);
var endOfSegment = segment.PositionOf(End);
if (endOfSegment != null)
{
var completeSegment = segment.Slice(0, segment.GetPosition(1, endOfSegment.Value));
if (this.Options.HasFlag(SegmentionOptions.SecondStartInvalid))
{
var secondStart = Starts.Select(start => completeSegment.PositionOf(start)).FirstOrDefault(start => start != null);
if (secondStart != null)
{
// Second start detected
return(SegmentationStatus.Invalid, buffer.Slice(0, secondStart.Value));
}
}
return(SegmentationStatus.Complete, completeSegment);
}
else if (this.MaxLength.HasValue && buffer.Length > this.MaxLength)
{
var leftover = buffer.Length % this.MaxLength.Value;
buffer = buffer.Slice(0, buffer.GetPosition(-leftover, buffer.End));
return(SegmentationStatus.Invalid, buffer);
}
}
return(SegmentationStatus.Incomplete, null);
}
protected override (SegmentationStatus status, ReadOnlySequence <byte>?segment) Read(ReadOnlySequence <byte> buffer)
{
var startOfSegment = Starts.Select(start => buffer.PositionOf(start)).FirstOrDefault(start => start != null);
if (startOfSegment != null)
{
var segment = buffer.Slice(startOfSegment.Value);
if (segment.Length >= FixedLength)
{
var completeSegment = segment.Slice(0, buffer.GetPosition(FixedLength, startOfSegment.Value));
if (this.Options.HasFlag(SegmentionOptions.SecondStartInvalid))
{
var secondStart = Starts.Select(start => completeSegment.PositionOf(start)).FirstOrDefault(start => start != null);
if (secondStart != null)
{
// Second start detected
return(SegmentationStatus.Invalid, buffer.Slice(0, secondStart.Value));
}
}
if (ExtensionDefinition != null)
{
var valueData = completeSegment.Slice(ExtensionDefinition.Postion, ExtensionDefinition.Length);
//TODO, drop the endian check... only support little and convert
var set = this.ExtensionDefinition.Endianness == Endianness.Little ? valueData.ToArray() : valueData.ToArray().Reverse().ToArray();
ulong extendedLength = 0;
for (var i = 0; i < this.ExtensionDefinition.Length; i++)
{
extendedLength |= (ulong)set[i] << (8 * i);
}
var actualLength = FixedLength + (long)extendedLength;
if (segment.Length < actualLength)
{
return(SegmentationStatus.Incomplete, buffer);
}
completeSegment = segment.Slice(0, buffer.GetPosition(actualLength, startOfSegment.Value));
}
return(SegmentationStatus.Complete, completeSegment);
}
}
else if (buffer.Length > this.FixedLength)
{
var leftover = buffer.Length % this.FixedLength;
buffer = buffer.Slice(0, buffer.GetPosition(-leftover, buffer.End));
return(SegmentationStatus.Invalid, buffer);
}
return(SegmentationStatus.Incomplete, buffer);
}
